Cleanup of mod_python references and other things

mod_python is more than deprecated and WSGI is the standard.

I started with removing mentions of mod_python and found there were a bunch of old and weird things that I'm pretty sure aren't needed anymore. Let me know if I'm wrong :)

* Apache config generator for mod_python
* specfiles for graphite-web, untouched for a long time. centos's graphite-web package is based on something entirely different
* a very old vendored carbon-relay and a specfile
* a duplicate (but older) index builder
* a script for generating a tarball, easy to replace with git/github

There's still some interesting stuff in `contrib` that I didn't want to touch because I have no idea if they still work.